High-voltage spinel LiNi0.5Mn1.5O4 for lithium-ion batteries: synthesis improvement using different thermal treatment

ALEJANDRA CALVO; MELINA COZZARIN ; JORGE THOMAS; SANSERVINO MIGUEL; ANTONELA CANNEVA; VISINTIN A.

Buenos Aires

Congreso; 20th Topical Meeting of the International Society of Electrochemistry Advances in Lithium and Hydrogen Electrochemical Systems for Energy Conversion and Storage; 2017

20th Topical Meeting of the International Society of Electrochemistry Advances in Lithium and Hydrogen Electrochemical Systems for Energy Conversion and Storage

Nowadays, technology advances have reached such a development level where the use of different kinds of renewable energies (wind, solar, geothermal, etc) is a reality on continuous growth. This fact requires solving the problem of a proper storage of the energy, usually generated as electricity. In that sense, lithium-ion batteries have become a worldwide recognized useful technology. One relevant issue for industrial processes is making batteries lighter and with high power densities . That would be an essential feature required for electrical vehicles. In that way, the challenge consists on working to improve the power density of active materials for cathodes as LiNi0.5Mn1.5O4, that has been tested as high-voltage cathode with discharge potential plateau of approximately 4.7 V versus lithium. , , This work presents synthesis and characterization of LiNi0.5Mn1.5O4 materials using the solid-state method, It is clear that high-temperature processes, unless using solar thermal, will eventually be replaced by low-temperature synthesis methods. For provides energy savings, with different thermal treatment: 1) First period of 8 hours at 350ºC and second period of 22 hs at 850ºC, 2) First period of 6 hours at 600ºC and second period of 16 hs at 850ºC, 3) First period of 6 hours at 600ºC and second period of 22 hs at 850ºC The materials have been tested electrochemically by charge-discharge cycling, cyclic voltammetry (CV), rate capability and electrochemical impedance spectroscopy (EIS). The samples have shown a discharge capacity at C/10 of 1) 136.4 mA.h/g, 2) 116.5 mA.h/g, 3) 135.8mA.h/g.The samples obtained are being characterized by X-Ray Photoelectron Spectroscopy (XPS) and the results are going to be used in order to improve the synthesis. XPS measurements have been helpful to optimize the synthesis process and design better active materials.